diff --git a/packages/astro/test/astro-directives.test.js b/packages/astro/test/astro-directives.test.js
index c4d868df3edf..80b4d32d1143 100644
--- a/packages/astro/test/astro-directives.test.js
+++ b/packages/astro/test/astro-directives.test.js
@@ -1,5 +1,5 @@
 import assert from 'node:assert/strict';
-import { before, describe, it } from 'node:test';
+import { after, before, describe, it } from 'node:test';
 import * as cheerio from 'cheerio';
 import { loadFixture } from './test-utils.js';
 
@@ -117,4 +117,52 @@ describe('Directives', async () => {
 		// Should not create Astro islands
 		assert.equal($('astro-island').length, 0);
 	});
+
+	it('set:html Fragment as slot (children)', async () => {
+		let res = await fixture.readFile('/set-html-children/index.html');
+		assert.equal(res.includes('Test'), true);
+	});
+});
+
+describe('set:html dev', () => {
+	/** @type {import('./test-utils').Fixture} */
+	let fixture;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/astro-directives/',
+		});
+	});
+
+	describe('Development', () => {
+		/** @type {import('./test-utils').DevServer} */
+		let devServer;
+
+		before(async () => {
+			devServer = await fixture.startDevServer();
+			globalThis.TEST_FETCH = (fetch, url, init) => {
+				return fetch(fixture.resolveUrl(url), init);
+			};
+		});
+
+		after(async () => {
+			await devServer.stop();
+		});
+
+		it('set:html can take a fetch()', async () => {
+			let res = await fixture.fetch('/set-html-fetch');
+			assert.equal(res.status, 200);
+			let html = await res.text();
+			const $ = cheerio.load(html);
+			assert.equal($('#fetched-html').length, 1);
+			assert.equal($('#fetched-html').text(), 'works');
+		});
+
+		it('set:html Fragment as slot (children) in dev', async () => {
+			let res = await fixture.fetch('/set-html-children');
+			assert.equal(res.status, 200);
+			let html = await res.text();
+			assert.equal(html.includes('Test'), true);
+		});
+	});
 });
diff --git a/packages/astro/test/astro-external-files.test.js b/packages/astro/test/astro-external-files.test.js
index 80adb5986d45..5903f189d9c7 100644
--- a/packages/astro/test/astro-external-files.test.js
+++ b/packages/astro/test/astro-external-files.test.js
@@ -6,12 +6,12 @@ describe('External file references', () => {
 	let fixture;
 
 	before(async () => {
-		fixture = await loadFixture({ root: './fixtures/astro-external-files/' });
+		fixture = await loadFixture({ root: './fixtures/astro-public/' });
 		await fixture.build();
 	});
 
 	it('Build with external reference', async () => {
-		const html = await fixture.readFile('/index.html');
+		const html = await fixture.readFile('/external-files/index.html');
 		assert.equal(html.includes('<script src="/external-file.js"'), true);
 	});
 });
diff --git a/packages/astro/test/astro-fallback.test.js b/packages/astro/test/astro-fallback.test.js
index bdd44afa4374..dccac0586431 100644
--- a/packages/astro/test/astro-fallback.test.js
+++ b/packages/astro/test/astro-fallback.test.js
@@ -8,13 +8,13 @@ describe('Dynamic component fallback', () => {
 
 	before(async () => {
 		fixture = await loadFixture({
-			root: './fixtures/astro-fallback',
+			root: './fixtures/astro-expr/',
 		});
 		await fixture.build();
 	});
 
 	it('Shows static content', async () => {
-		const html = await fixture.readFile('/index.html');
+		const html = await fixture.readFile('/fallback/index.html');
 		const $ = cheerio.load(html);
 		assert.equal($('#fallback').text(), 'static');
 	});
diff --git a/packages/astro/test/astro-generator.test.js b/packages/astro/test/astro-generator.test.js
index df1f1ffa5db9..592f5dde4892 100644
--- a/packages/astro/test/astro-generator.test.js
+++ b/packages/astro/test/astro-generator.test.js
@@ -8,14 +8,14 @@ describe('Astro generator', () => {
 
 	before(async () => {
 		fixture = await loadFixture({
-			root: './fixtures/astro-generator/',
+			root: './fixtures/astro-basic/',
 		});
 		await fixture.build();
 	});
 
 	describe('build', () => {
 		it('Defines Astro.generator', async () => {
-			const html = await fixture.readFile(`/index.html`);
+			const html = await fixture.readFile(`/generator/index.html`);
 			const $ = cheerio.load(html);
 
 			assert.match($('meta[name="generator"]').attr('content'), /^Astro v/);
diff --git a/packages/astro/test/astro-slot-with-client.test.js b/packages/astro/test/astro-slot-with-client.test.js
index cf762a9db051..4cdba630ef85 100644
--- a/packages/astro/test/astro-slot-with-client.test.js
+++ b/packages/astro/test/astro-slot-with-client.test.js
@@ -8,18 +8,18 @@ describe('Slots with client: directives', () => {
 	let fixture;
 
 	before(async () => {
-		fixture = await loadFixture({ root: './fixtures/astro-slot-with-client/' });
+		fixture = await loadFixture({ root: './fixtures/astro-expr/' });
 		await fixture.build();
 	});
 
 	it('Tags of dynamic tags works', async () => {
-		const html = await fixture.readFile('/index.html');
+		const html = await fixture.readFile('/slot-with-client/index.html');
 		const $ = cheerio.load(html);
 		assert.equal($('script').length, 2);
 	});
 
 	it('Astro slot tags are kept', async () => {
-		const html = await fixture.readFile('/index.html');
+		const html = await fixture.readFile('/slot-with-client/index.html');
 		const $ = cheerio.load(html);
 		assert.equal($('astro-slot').length, 1);
 	});
diff --git a/packages/astro/test/core-image-svg.test.js b/packages/astro/test/core-image-svg.test.js
index b7cad2f1a4a8..a50fb7b33ff9 100644
--- a/packages/astro/test/core-image-svg.test.js
+++ b/packages/astro/test/core-image-svg.test.js
@@ -159,7 +159,18 @@ describe('astro:assets - SVG Components', () => {
 
 		before(async () => {
 			optimizedFixture = await loadFixture({
-				root: './fixtures/core-image-svg-optimized/',
+				root: './fixtures/core-image-svg/',
+				experimental: {
+					svgo: {
+						plugins: [
+							'preset-default',
+							{
+								name: 'removeViewBox',
+								active: false,
+							},
+						],
+					},
+				},
 			});
 
 			optimizedDevServer = await optimizedFixture.startDevServer();
diff --git a/packages/astro/test/core-image.test.js b/packages/astro/test/core-image.test.js
index b4d671c67813..13e94076b0f4 100644
--- a/packages/astro/test/core-image.test.js
+++ b/packages/astro/test/core-image.test.js
@@ -888,9 +888,14 @@ describe('astro:image', () => {
 	describe('support base option correctly', () => {
 		before(async () => {
 			fixture = await loadFixture({
-				root: './fixtures/core-image-base/',
+				root: './fixtures/core-image-ssg/',
 				image: {
 					service: testImageService(),
+					domains: [
+						'astro.build',
+						'avatars.githubusercontent.com',
+						'kaleidoscopic-biscotti-6fe98c.netlify.app',
+					],
 				},
 				base: '/blog',
 			});
diff --git a/packages/astro/test/css-order.test.js b/packages/astro/test/css-order.test.js
index 2a46136d90e0..9ade2cb999c6 100644
--- a/packages/astro/test/css-order.test.js
+++ b/packages/astro/test/css-order.test.js
@@ -116,13 +116,13 @@ describe('CSS production ordering', () => {
 
 		before(async () => {
 			fixture = await loadFixture({
-				root: './fixtures/css-order-transparent/',
+				root: './fixtures/css-order-layout/',
 			});
 			await fixture.build();
 		});
 
 		it('should compile styles in the same order as they are found', async () => {
-			const html = await fixture.readFile('/index.html');
+			const html = await fixture.readFile('/transparent/index.html');
 
 			// The component declares red background first, then yellow
 			assert.match(html, /body\{background:red\}body\{background:#ff0/);
diff --git a/packages/astro/test/fixtures/astro-generator/src/pages/index.astro b/packages/astro/test/fixtures/astro-basic/src/pages/generator.astro
similarity index 100%
rename from packages/astro/test/fixtures/astro-generator/src/pages/index.astro
rename to packages/astro/test/fixtures/astro-basic/src/pages/generator.astro
diff --git a/packages/astro/test/fixtures/set-html/public/test.html b/packages/astro/test/fixtures/astro-directives/public/test.html
similarity index 100%
rename from packages/astro/test/fixtures/set-html/public/test.html
rename to packages/astro/test/fixtures/astro-directives/public/test.html
diff --git a/packages/astro/test/fixtures/set-html/components/Slot.astro b/packages/astro/test/fixtures/astro-directives/src/components/Slot.astro
similarity index 100%
rename from packages/astro/test/fixtures/set-html/components/Slot.astro
rename to packages/astro/test/fixtures/astro-directives/src/components/Slot.astro
diff --git a/packages/astro/test/fixtures/set-html/src/pages/children.astro b/packages/astro/test/fixtures/astro-directives/src/pages/set-html-children.astro
similarity index 88%
rename from packages/astro/test/fixtures/set-html/src/pages/children.astro
rename to packages/astro/test/fixtures/astro-directives/src/pages/set-html-children.astro
index 3ef5c5b0b944..c539bc3f6f97 100644
--- a/packages/astro/test/fixtures/set-html/src/pages/children.astro
+++ b/packages/astro/test/fixtures/astro-directives/src/pages/set-html-children.astro
@@ -1,5 +1,5 @@
 ---
-import Slot from '../../components/Slot.astro';
+import Slot from '../components/Slot.astro';
 ---
 
 <html>
diff --git a/packages/astro/test/fixtures/set-html/src/pages/fetch.astro b/packages/astro/test/fixtures/astro-directives/src/pages/set-html-fetch.astro
similarity index 100%
rename from packages/astro/test/fixtures/set-html/src/pages/fetch.astro
rename to packages/astro/test/fixtures/astro-directives/src/pages/set-html-fetch.astro
diff --git a/packages/astro/test/fixtures/set-html/src/pages/index.astro b/packages/astro/test/fixtures/astro-directives/src/pages/set-html-types.astro
similarity index 100%
rename from packages/astro/test/fixtures/set-html/src/pages/index.astro
rename to packages/astro/test/fixtures/astro-directives/src/pages/set-html-types.astro
diff --git a/packages/astro/test/fixtures/astro-fallback/src/components/Client.jsx b/packages/astro/test/fixtures/astro-expr/src/components/Client.jsx
similarity index 100%
rename from packages/astro/test/fixtures/astro-fallback/src/components/Client.jsx
rename to packages/astro/test/fixtures/astro-expr/src/components/Client.jsx
diff --git a/packages/astro/test/fixtures/astro-slot-with-client/src/components/Slotted.astro b/packages/astro/test/fixtures/astro-expr/src/components/Slotted.astro
similarity index 100%
rename from packages/astro/test/fixtures/astro-slot-with-client/src/components/Slotted.astro
rename to packages/astro/test/fixtures/astro-expr/src/components/Slotted.astro
diff --git a/packages/astro/test/fixtures/astro-slot-with-client/src/components/Thing.jsx b/packages/astro/test/fixtures/astro-expr/src/components/Thing.jsx
similarity index 100%
rename from packages/astro/test/fixtures/astro-slot-with-client/src/components/Thing.jsx
rename to packages/astro/test/fixtures/astro-expr/src/components/Thing.jsx
diff --git a/packages/astro/test/fixtures/astro-fallback/src/pages/index.astro b/packages/astro/test/fixtures/astro-expr/src/pages/fallback.astro
similarity index 100%
rename from packages/astro/test/fixtures/astro-fallback/src/pages/index.astro
rename to packages/astro/test/fixtures/astro-expr/src/pages/fallback.astro
diff --git a/packages/astro/test/fixtures/astro-slot-with-client/src/pages/index.astro b/packages/astro/test/fixtures/astro-expr/src/pages/slot-with-client.astro
similarity index 100%
rename from packages/astro/test/fixtures/astro-slot-with-client/src/pages/index.astro
rename to packages/astro/test/fixtures/astro-expr/src/pages/slot-with-client.astro
diff --git a/packages/astro/test/fixtures/astro-external-files/package.json b/packages/astro/test/fixtures/astro-external-files/package.json
deleted file mode 100644
index 5f0a99bcfebe..000000000000
--- a/packages/astro/test/fixtures/astro-external-files/package.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "name": "@test/astro-external-files",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  }
-}
diff --git a/packages/astro/test/fixtures/astro-fallback/astro.config.mjs b/packages/astro/test/fixtures/astro-fallback/astro.config.mjs
deleted file mode 100644
index a8afbd82f250..000000000000
--- a/packages/astro/test/fixtures/astro-fallback/astro.config.mjs
+++ /dev/null
@@ -1,7 +0,0 @@
-import preact from '@astrojs/preact';
-import { defineConfig } from 'astro/config';
-
-// https://astro.build/config
-export default defineConfig({
-	integrations: [preact()],
-});
diff --git a/packages/astro/test/fixtures/astro-fallback/package.json b/packages/astro/test/fixtures/astro-fallback/package.json
deleted file mode 100644
index c60672a50d9b..000000000000
--- a/packages/astro/test/fixtures/astro-fallback/package.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "name": "@test/astro-fallback",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "@astrojs/preact": "workspace:*",
-    "astro": "workspace:*",
-    "preact": "^10.29.0"
-  }
-}
diff --git a/packages/astro/test/fixtures/astro-generator/package.json b/packages/astro/test/fixtures/astro-generator/package.json
deleted file mode 100644
index 5fe696624cba..000000000000
--- a/packages/astro/test/fixtures/astro-generator/package.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "name": "@test/astro-generator",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  }
-}
diff --git a/packages/astro/test/fixtures/astro-external-files/public/external-file.js b/packages/astro/test/fixtures/astro-public/public/external-file.js
similarity index 100%
rename from packages/astro/test/fixtures/astro-external-files/public/external-file.js
rename to packages/astro/test/fixtures/astro-public/public/external-file.js
diff --git a/packages/astro/test/fixtures/astro-external-files/src/pages/index.astro b/packages/astro/test/fixtures/astro-public/src/pages/external-files.astro
similarity index 100%
rename from packages/astro/test/fixtures/astro-external-files/src/pages/index.astro
rename to packages/astro/test/fixtures/astro-public/src/pages/external-files.astro
diff --git a/packages/astro/test/fixtures/astro-slot-with-client/astro.config.mjs b/packages/astro/test/fixtures/astro-slot-with-client/astro.config.mjs
deleted file mode 100644
index d3664dcde950..000000000000
--- a/packages/astro/test/fixtures/astro-slot-with-client/astro.config.mjs
+++ /dev/null
@@ -1,8 +0,0 @@
-import preact from '@astrojs/preact';
-import { defineConfig } from 'astro/config';
-
-export default defineConfig({
-	integrations: [
-		preact()
-	]
-});
diff --git a/packages/astro/test/fixtures/astro-slot-with-client/package.json b/packages/astro/test/fixtures/astro-slot-with-client/package.json
deleted file mode 100644
index 8738dc97d4de..000000000000
--- a/packages/astro/test/fixtures/astro-slot-with-client/package.json
+++ /dev/null
@@ -1,9 +0,0 @@
-{
-  "name": "@test/astro-slot-with-client",
-  "private": true,
-  "dependencies": {
-    "@astrojs/preact": "workspace:*",
-    "astro": "workspace:*",
-    "preact": "^10.29.0"
-  }
-}
diff --git a/packages/astro/test/fixtures/content-static-paths-integration/package.json b/packages/astro/test/fixtures/content-static-paths-integration/package.json
index 92f141a6f87d..6e15b0eeb2e2 100644
--- a/packages/astro/test/fixtures/content-static-paths-integration/package.json
+++ b/packages/astro/test/fixtures/content-static-paths-integration/package.json
@@ -3,7 +3,7 @@
   "version": "0.0.0",
   "private": true,
   "dependencies": {
-    "astro": "workspace:*",
-    "@astrojs/mdx": "workspace:*"
+    "@astrojs/mdx": "workspace:*",
+    "astro": "workspace:*"
   }
 }
diff --git a/packages/astro/test/fixtures/content-static-paths-integration/src/content.config.ts b/packages/astro/test/fixtures/content-static-paths-integration/src/content.config.ts
index a880cc1053fd..6df4d99e5c60 100644
--- a/packages/astro/test/fixtures/content-static-paths-integration/src/content.config.ts
+++ b/packages/astro/test/fixtures/content-static-paths-integration/src/content.config.ts
@@ -13,4 +13,4 @@ const blog = defineCollection({
 	}),
 });
 
-export const collections = { blog };
+export const collections = { blog };
\ No newline at end of file
diff --git a/packages/astro/test/fixtures/core-image-base/package.json b/packages/astro/test/fixtures/core-image-base/package.json
deleted file mode 100644
index a5c4cd6f34bd..000000000000
--- a/packages/astro/test/fixtures/core-image-base/package.json
+++ /dev/null
@@ -1,11 +0,0 @@
-{
-  "name": "@test/core-image-base",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  },
-  "exports": {
-    "./service": "./src/service.ts"
-  }
-}
diff --git a/packages/astro/test/fixtures/core-image-base/src/assets/penguin1.jpg b/packages/astro/test/fixtures/core-image-base/src/assets/penguin1.jpg
deleted file mode 100644
index 1a8986ac5092..000000000000
Binary files a/packages/astro/test/fixtures/core-image-base/src/assets/penguin1.jpg and /dev/null differ
diff --git a/packages/astro/test/fixtures/core-image-base/src/assets/penguin2.jpg b/packages/astro/test/fixtures/core-image-base/src/assets/penguin2.jpg
deleted file mode 100644
index e859ac3c992f..000000000000
Binary files a/packages/astro/test/fixtures/core-image-base/src/assets/penguin2.jpg and /dev/null differ
diff --git a/packages/astro/test/fixtures/core-image-base/src/content.config.ts b/packages/astro/test/fixtures/core-image-base/src/content.config.ts
deleted file mode 100644
index 466ced827049..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/content.config.ts
+++ /dev/null
@@ -1,18 +0,0 @@
-import { defineCollection } from 'astro:content';
-import { z } from 'astro/zod';
-import { glob } from "astro/loaders";
-
-const blogCollection = defineCollection({
-  loader: glob({ pattern: '**/*.{md,mdx}', base: './src/content/blog' }),
-  schema: ({image}) => z.object({
-    title: z.string(),
-    image: image(),
-		cover: z.object({
-			image: image()
-		})
-  }),
-});
-
-export const collections = {
-	blog: blogCollection
-};
diff --git a/packages/astro/test/fixtures/core-image-base/src/content/blog/one.md b/packages/astro/test/fixtures/core-image-base/src/content/blog/one.md
deleted file mode 100644
index d449290ef6d6..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/content/blog/one.md
+++ /dev/null
@@ -1,10 +0,0 @@
----
-title: One
-image: ../../assets/penguin2.jpg
-cover:
-  image: ../../assets/penguin1.jpg
----
-
-# A post
-
-text here
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/alias.astro b/packages/astro/test/fixtures/core-image-base/src/pages/alias.astro
deleted file mode 100644
index 10990dbe3e9b..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/alias.astro
+++ /dev/null
@@ -1,5 +0,0 @@
----
-import image from "~/assets/penguin1.jpg";
----
-
-<img src={image.src} width={image.width} height={image.height} alt="A penguin!" />
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/aliasMarkdown.md b/packages/astro/test/fixtures/core-image-base/src/pages/aliasMarkdown.md
deleted file mode 100644
index 048a79bdd5cf..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/aliasMarkdown.md
+++ /dev/null
@@ -1,3 +0,0 @@
-![A penguin](~/assets/penguin1.jpg)
-
-A penguin
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/blog/[...slug].astro b/packages/astro/test/fixtures/core-image-base/src/pages/blog/[...slug].astro
deleted file mode 100644
index 45dfb8ab9946..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/blog/[...slug].astro
+++ /dev/null
@@ -1,32 +0,0 @@
----
-import { getImage } from 'astro:assets';
-import { getCollection, render } from 'astro:content';
-
-export async function getStaticPaths() {
-	const blogEntries = await getCollection('blog');
-  return blogEntries.map(entry => ({
-    params: { slug: entry.id }, props: { entry },
-  }));
-}
-
-const { entry } = Astro.props;
-const { Content } = await render(entry);
----
-<html>
-	<head>
-		<title>Testing</title>
-	</head>
-	<body>
-		<h1>Testing</h1>
-
-		<div id="direct-image">
-			<img src={entry.data.image.src} width={entry.data.image.width} height={entry.data.image.height} />
-		</div>
-
-		<div id="nested-image">
-			<img src={entry.data.cover.image.src} width={entry.data.cover.image.width} height={entry.data.cover.image.height} />
-		</div>
-
-		<Content />
-	</body>
-</html>
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/format.astro b/packages/astro/test/fixtures/core-image-base/src/pages/format.astro
deleted file mode 100644
index d2b165d892b5..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/format.astro
+++ /dev/null
@@ -1,18 +0,0 @@
----
-import { Image } from 'astro:assets';
-import myImage from "../assets/penguin1.jpg";
----
-<html>
-<head>
-
-</head>
-<body>
-	<div id="no-format">
-		<Image src={myImage} alt="a penguin" />
-	</div>
-
-	<div id="format-avif">
-		<Image src={myImage} alt="a penguin" format="avif" />
-	</div>
-</body>
-</html>
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/get-image.astro b/packages/astro/test/fixtures/core-image-base/src/pages/get-image.astro
deleted file mode 100644
index d83b1fd8ee78..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/get-image.astro
+++ /dev/null
@@ -1,8 +0,0 @@
----
-import { getImage } from "astro:assets";
-import image from "../assets/penguin2.jpg";
-
-const myImage = await getImage({ src: image, width: 207, height: 243, alt: 'a penguin' });
----
-
-<img src={myImage.src} {...myImage.attributes} />
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/index.astro b/packages/astro/test/fixtures/core-image-base/src/pages/index.astro
deleted file mode 100644
index d7f9b05519a5..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/index.astro
+++ /dev/null
@@ -1,18 +0,0 @@
----
-import { Image } from 'astro:assets';
-import myImage from "../assets/penguin1.jpg";
----
-<html>
-<head>
-
-</head>
-<body>
-	<div id="local">
-		<Image src={myImage} alt="a penguin" />
-	</div>
-	
-	<div id="remote">
-		<Image src="https://avatars.githubusercontent.com/u/622227?s=64" alt="fred" width="48" height="48" />
-	</div>
-</body>
-</html>
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/post.md b/packages/astro/test/fixtures/core-image-base/src/pages/post.md
deleted file mode 100644
index 98da01ce41b2..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/post.md
+++ /dev/null
@@ -1,3 +0,0 @@
-![My article cover](../assets/penguin1.jpg)
-
-Image worked
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/quality.astro b/packages/astro/test/fixtures/core-image-base/src/pages/quality.astro
deleted file mode 100644
index 706bb6766934..000000000000
--- a/packages/astro/test/fixtures/core-image-base/src/pages/quality.astro
+++ /dev/null
@@ -1,22 +0,0 @@
----
-import { Image } from 'astro:assets';
-import myImage from "../assets/penguin1.jpg";
----
-<html>
-<head>
-
-</head>
-<body>
-	<div id="no-quality">
-		<Image src={myImage} alt="a penguin" />
-	</div>
-
-	<div id="quality-low">
-		<Image src={myImage} alt="a penguin" quality="low" />
-	</div>
-
-	<div id="quality-num">
-		<Image src={myImage} alt="a penguin" quality="70" />
-	</div>
-</body>
-</html>
diff --git a/packages/astro/test/fixtures/core-image-base/tsconfig.json b/packages/astro/test/fixtures/core-image-base/tsconfig.json
deleted file mode 100644
index 1854f60e49c2..000000000000
--- a/packages/astro/test/fixtures/core-image-base/tsconfig.json
+++ /dev/null
@@ -1,12 +0,0 @@
-{
-  "extends": "astro/tsconfigs/strict",
-  "compilerOptions": {
-    "paths": {
-      "~/assets/*": [
-        "src/assets/*"
-      ]
-    },
-  },
-  "include": [".astro/types.d.ts", "**/*"],
-  "exclude": ["dist"]
-}
diff --git a/packages/astro/test/fixtures/core-image-base/src/pages/direct.astro b/packages/astro/test/fixtures/core-image-ssg/src/pages/direct.astro
similarity index 100%
rename from packages/astro/test/fixtures/core-image-base/src/pages/direct.astro
rename to packages/astro/test/fixtures/core-image-ssg/src/pages/direct.astro
diff --git a/packages/astro/test/fixtures/core-image-svg-optimized/astro.config.mjs b/packages/astro/test/fixtures/core-image-svg-optimized/astro.config.mjs
deleted file mode 100644
index c26e4cbdc1e3..000000000000
--- a/packages/astro/test/fixtures/core-image-svg-optimized/astro.config.mjs
+++ /dev/null
@@ -1,15 +0,0 @@
-import { defineConfig } from 'astro/config';
-
-export default defineConfig({
-	experimental: {
-		svgo: {
-			plugins: [
-				'preset-default',
-				{
-					name: 'removeViewBox',
-					active: false,
-				},
-			],
-		},
-	},
-});
diff --git a/packages/astro/test/fixtures/core-image-svg-optimized/package.json b/packages/astro/test/fixtures/core-image-svg-optimized/package.json
deleted file mode 100644
index 4557b402af29..000000000000
--- a/packages/astro/test/fixtures/core-image-svg-optimized/package.json
+++ /dev/null
@@ -1,11 +0,0 @@
-{
-  "name": "@test/core-image-svg-optimized",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  },
-  "scripts": {
-    "dev": "astro dev"
-  }
-}
diff --git a/packages/astro/test/fixtures/core-image-svg-optimized/tsconfig.json b/packages/astro/test/fixtures/core-image-svg-optimized/tsconfig.json
deleted file mode 100644
index 51747eeb3102..000000000000
--- a/packages/astro/test/fixtures/core-image-svg-optimized/tsconfig.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "extends": "astro/tsconfigs/strict",
-  "compilerOptions": {
-    "paths": {
-      "~/assets/*": [
-        "src/assets/*"
-      ]
-    },
-  }
-}
diff --git a/packages/astro/test/fixtures/core-image-svg-optimized/src/assets/unoptimized.svg b/packages/astro/test/fixtures/core-image-svg/src/assets/unoptimized.svg
similarity index 100%
rename from packages/astro/test/fixtures/core-image-svg-optimized/src/assets/unoptimized.svg
rename to packages/astro/test/fixtures/core-image-svg/src/assets/unoptimized.svg
diff --git a/packages/astro/test/fixtures/core-image-svg-optimized/src/pages/optimized.astro b/packages/astro/test/fixtures/core-image-svg/src/pages/optimized.astro
similarity index 100%
rename from packages/astro/test/fixtures/core-image-svg-optimized/src/pages/optimized.astro
rename to packages/astro/test/fixtures/core-image-svg/src/pages/optimized.astro
diff --git a/packages/astro/test/fixtures/core-image/src/pages/outsideProject.astro b/packages/astro/test/fixtures/core-image/src/pages/outsideProject.astro
index 268b44741302..2ca5803bcfa6 100644
--- a/packages/astro/test/fixtures/core-image/src/pages/outsideProject.astro
+++ b/packages/astro/test/fixtures/core-image/src/pages/outsideProject.astro
@@ -1,6 +1,6 @@
 ---
 import { Image } from "astro:assets";
-import imageOutsideProject from "../../../core-image-base/src/assets/penguin1.jpg";
+import imageOutsideProject from "../../../core-image-ssg/src/assets/penguin1.jpg";
 ---
 
 <Image src={imageOutsideProject} alt="outside project" />
diff --git a/packages/astro/test/fixtures/css-order-transparent/src/components/Item.astro b/packages/astro/test/fixtures/css-order-layout/src/components/Item.astro
similarity index 100%
rename from packages/astro/test/fixtures/css-order-transparent/src/components/Item.astro
rename to packages/astro/test/fixtures/css-order-layout/src/components/Item.astro
diff --git a/packages/astro/test/fixtures/css-order-transparent/src/pages/index.astro b/packages/astro/test/fixtures/css-order-layout/src/pages/transparent.astro
similarity index 100%
rename from packages/astro/test/fixtures/css-order-transparent/src/pages/index.astro
rename to packages/astro/test/fixtures/css-order-layout/src/pages/transparent.astro
diff --git a/packages/astro/test/fixtures/css-order-transparent/astro.config.mjs b/packages/astro/test/fixtures/css-order-transparent/astro.config.mjs
deleted file mode 100644
index 86dbfb924824..000000000000
--- a/packages/astro/test/fixtures/css-order-transparent/astro.config.mjs
+++ /dev/null
@@ -1,3 +0,0 @@
-import { defineConfig } from 'astro/config';
-
-export default defineConfig({});
diff --git a/packages/astro/test/fixtures/css-order-transparent/package.json b/packages/astro/test/fixtures/css-order-transparent/package.json
deleted file mode 100644
index 9edc472a0d29..000000000000
--- a/packages/astro/test/fixtures/css-order-transparent/package.json
+++ /dev/null
@@ -1,7 +0,0 @@
-{
-  "name": "@test/css-order-transparent",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  }
-}
diff --git a/packages/astro/test/fixtures/set-html/package.json b/packages/astro/test/fixtures/set-html/package.json
deleted file mode 100644
index c40fcd8acf41..000000000000
--- a/packages/astro/test/fixtures/set-html/package.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "name": "@test/set-html",
-  "version": "1.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  }
-}
diff --git a/packages/astro/test/fixtures/ssr-env/astro.config.mjs b/packages/astro/test/fixtures/ssr-env/astro.config.mjs
deleted file mode 100644
index 42f10a57298d..000000000000
--- a/packages/astro/test/fixtures/ssr-env/astro.config.mjs
+++ /dev/null
@@ -1,5 +0,0 @@
-import preact from '@astrojs/preact';
-
-export default {
-	integrations: [preact()]
-}
diff --git a/packages/astro/test/fixtures/ssr-env/package.json b/packages/astro/test/fixtures/ssr-env/package.json
deleted file mode 100644
index ab377aadccc2..000000000000
--- a/packages/astro/test/fixtures/ssr-env/package.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "name": "@test/ssr-env",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "@astrojs/preact": "workspace:*",
-    "astro": "workspace:*",
-    "preact": "^10.29.0"
-  }
-}
diff --git a/packages/astro/test/fixtures/ssr-markdown/package.json b/packages/astro/test/fixtures/ssr-markdown/package.json
deleted file mode 100644
index 4c76381919b1..000000000000
--- a/packages/astro/test/fixtures/ssr-markdown/package.json
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "name": "@test/ssr-markdown",
-  "version": "0.0.0",
-  "private": true,
-  "dependencies": {
-    "astro": "workspace:*"
-  }
-}
diff --git a/packages/astro/test/fixtures/ssr-markdown/src/layouts/Base.astro b/packages/astro/test/fixtures/ssr-prerender/src/layouts/Base.astro
similarity index 100%
rename from packages/astro/test/fixtures/ssr-markdown/src/layouts/Base.astro
rename to packages/astro/test/fixtures/ssr-prerender/src/layouts/Base.astro
diff --git a/packages/astro/test/fixtures/ssr-markdown/src/pages/post.md b/packages/astro/test/fixtures/ssr-prerender/src/pages/post.md
similarity index 100%
rename from packages/astro/test/fixtures/ssr-markdown/src/pages/post.md
rename to packages/astro/test/fixtures/ssr-prerender/src/pages/post.md
diff --git a/packages/astro/test/fixtures/ssr-env/src/components/Env.jsx b/packages/astro/test/fixtures/ssr-scripts/src/components/Env.jsx
similarity index 100%
rename from packages/astro/test/fixtures/ssr-env/src/components/Env.jsx
rename to packages/astro/test/fixtures/ssr-scripts/src/components/Env.jsx
diff --git a/packages/astro/test/fixtures/ssr-env/src/pages/ssr.astro b/packages/astro/test/fixtures/ssr-scripts/src/pages/ssr.astro
similarity index 100%
rename from packages/astro/test/fixtures/ssr-env/src/pages/ssr.astro
rename to packages/astro/test/fixtures/ssr-scripts/src/pages/ssr.astro
diff --git a/packages/astro/test/set-html.test.js b/packages/astro/test/set-html.test.js
deleted file mode 100644
index 04655d80cb6c..000000000000
--- a/packages/astro/test/set-html.test.js
+++ /dev/null
@@ -1,57 +0,0 @@
-import assert from 'node:assert/strict';
-import { after, before, describe, it } from 'node:test';
-import * as cheerio from 'cheerio';
-import { loadFixture } from './test-utils.js';
-
-describe('set:html', () => {
-	/** @type {import('./test-utils').Fixture} */
-	let fixture;
-
-	before(async () => {
-		fixture = await loadFixture({
-			root: './fixtures/set-html/',
-		});
-	});
-
-	describe('Development', () => {
-		/** @type {import('./test-utils').DevServer} */
-		let devServer;
-
-		before(async () => {
-			devServer = await fixture.startDevServer();
-			globalThis.TEST_FETCH = (fetch, url, init) => {
-				return fetch(fixture.resolveUrl(url), init);
-			};
-		});
-
-		after(async () => {
-			await devServer.stop();
-		});
-
-		it('can take a fetch()', async () => {
-			let res = await fixture.fetch('/fetch');
-			assert.equal(res.status, 200);
-			let html = await res.text();
-			const $ = cheerio.load(html);
-			assert.equal($('#fetched-html').length, 1);
-			assert.equal($('#fetched-html').text(), 'works');
-		});
-		it('test Fragment when Fragment is as a slot', async () => {
-			let res = await fixture.fetch('/children');
-			assert.equal(res.status, 200);
-			let html = await res.text();
-			assert.equal(html.includes('Test'), true);
-		});
-	});
-
-	describe('Build', () => {
-		before(async () => {
-			await fixture.build();
-		});
-
-		it('test Fragment when Fragment is as a slot', async () => {
-			let res = await fixture.readFile('/children/index.html');
-			assert.equal(res.includes('Test'), true);
-		});
-	});
-});
diff --git a/packages/astro/test/ssr-env.test.js b/packages/astro/test/ssr-env.test.js
deleted file mode 100644
index 7da190736768..000000000000
--- a/packages/astro/test/ssr-env.test.js
+++ /dev/null
@@ -1,28 +0,0 @@
-import assert from 'node:assert/strict';
-import { before, describe, it } from 'node:test';
-import * as cheerio from 'cheerio';
-import testAdapter from './test-adapter.js';
-import { loadFixture } from './test-utils.js';
-
-describe('SSR Environment Variables', () => {
-	/** @type {import('./test-utils').Fixture} */
-	let fixture;
-
-	before(async () => {
-		fixture = await loadFixture({
-			root: './fixtures/ssr-env/',
-			output: 'server',
-			adapter: testAdapter(),
-		});
-		await fixture.build();
-	});
-
-	it('import.meta.env.SSR is true', async () => {
-		const app = await fixture.loadTestAdapterApp();
-		const request = new Request('http://example.com/ssr');
-		const response = await app.render(request);
-		const html = await response.text();
-		const $ = cheerio.load(html);
-		assert.equal($('#ssr').text(), 'true');
-	});
-});
diff --git a/packages/astro/test/ssr-markdown.test.js b/packages/astro/test/ssr-markdown.test.js
index 286891790316..c275c12157f3 100644
--- a/packages/astro/test/ssr-markdown.test.js
+++ b/packages/astro/test/ssr-markdown.test.js
@@ -10,7 +10,7 @@ describe('Markdown pages in SSR', () => {
 
 	before(async () => {
 		fixture = await loadFixture({
-			root: './fixtures/ssr-markdown/',
+			root: './fixtures/ssr-prerender/',
 			output: 'server',
 			adapter: testAdapter(),
 		});
diff --git a/packages/astro/test/ssr-scripts.test.js b/packages/astro/test/ssr-scripts.test.js
index 5afa2a25bc50..e4e84e053e28 100644
--- a/packages/astro/test/ssr-scripts.test.js
+++ b/packages/astro/test/ssr-scripts.test.js
@@ -1,5 +1,6 @@
 import assert from 'node:assert/strict';
 import { before, describe, it } from 'node:test';
+import * as cheerio from 'cheerio';
 import testAdapter from './test-adapter.js';
 import { loadFixture } from './test-utils.js';
 
@@ -23,4 +24,13 @@ describe('SSR Hydrated component scripts', () => {
 		const assets = app.manifest.assets;
 		assert.ok(assets.size > 0);
 	});
+
+	it('import.meta.env.SSR is true', async () => {
+		const app = await fixture.loadTestAdapterApp();
+		const request = new Request('http://example.com/ssr');
+		const response = await app.render(request);
+		const html = await response.text();
+		const $ = cheerio.load(html);
+		assert.equal($('#ssr').text(), 'true');
+	});
 });
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 7867b4d32a99..3cb321de580f 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -2219,30 +2219,6 @@ importers:
         specifier: ^10.29.0
         version: 10.29.0
 
-  packages/astro/test/fixtures/astro-external-files:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
-  packages/astro/test/fixtures/astro-fallback:
-    dependencies:
-      '@astrojs/preact':
-        specifier: workspace:*
-        version: link:../../../../integrations/preact
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-      preact:
-        specifier: ^10.29.0
-        version: 10.29.0
-
-  packages/astro/test/fixtures/astro-generator:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/astro-get-static-paths:
     dependencies:
       astro:
@@ -2435,18 +2411,6 @@ importers:
         specifier: ^4.2.2
         version: 4.2.2
 
-  packages/astro/test/fixtures/astro-slot-with-client:
-    dependencies:
-      '@astrojs/preact':
-        specifier: workspace:*
-        version: link:../../../../integrations/preact
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-      preact:
-        specifier: ^10.29.0
-        version: 10.29.0
-
   packages/astro/test/fixtures/astro-slots:
     dependencies:
       astro:
@@ -2814,12 +2778,6 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
-  packages/astro/test/fixtures/core-image-base:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/core-image-data-url:
     dependencies:
       astro:
@@ -2916,12 +2874,6 @@ importers:
         specifier: ^19.2.4
         version: 19.2.4(react@19.2.4)
 
-  packages/astro/test/fixtures/core-image-svg-optimized:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/core-image-unconventional-settings:
     dependencies:
       astro:
@@ -3062,12 +3014,6 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
-  packages/astro/test/fixtures/css-order-transparent:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/custom-404-html:
     dependencies:
       astro:
@@ -3909,12 +3855,6 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
-  packages/astro/test/fixtures/set-html:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/slots-preact:
     dependencies:
       '@astrojs/mdx':
@@ -4077,24 +4017,6 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
-  packages/astro/test/fixtures/ssr-env:
-    dependencies:
-      '@astrojs/preact':
-        specifier: workspace:*
-        version: link:../../../../integrations/preact
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-      preact:
-        specifier: ^10.29.0
-        version: 10.29.0
-
-  packages/astro/test/fixtures/ssr-markdown:
-    dependencies:
-      astro:
-        specifier: workspace:*
-        version: link:../../..
-
   packages/astro/test/fixtures/ssr-partytown:
     dependencies:
       '@astrojs/partytown':